Earlier quoted context omitted.
Your designers are working with abstract models. They are thinking about problems at a conceptual model, they are not putting up structures and seeing if they work.
code is also an abstract model. The CAD designers absolutely test if things work. Why do you think almost every engineering bureau has 3D printers.
Sure, but it is not the only one. You are allowed to think at other levels, and it can be quite useful, especially on larger systems.